Flibanserin and Regulatory Failure

On August 18th, 2015, the FDA approved flibanserin (brand name Addyi), a purported aphrodisiac that can drop blood pressure so precipitously that users sometimes pass out and require medical intervention to regain consciousness. The labelling for flibanserin indicates that it is for:

the treatment of premenopausal women with acquired, generalized hypoactive sexual desire disorder (HSDD), as characterized by low sexual desire that causes marked distress or interpersonal difficulty and is NOT due to:

• A co-existing medical or psychiatric condition,

• Problems within the relationship, or

• The effects of a medication or other drug substance.

Focus for a moment on “Low sexual desire that causes marked distress or interpersonal difficulty”. So a woman upset by a belittling spouse who wants sex more often than she does is eligible for a prescription drug? It gives a whole new meaning to the term “drugs of abuse.” Note that even if the putative patient isn’t distressed, she is still eligible for being drugged if her partner is creating interpersonal difficulty. Here’s a thought – why not sedate him instead?

Not every partner is a jerk, and there are certainly women distressed by loss of libido, but flibanserin isn’t the answer for these women either. As an aphrodisiac, it’s no great shakes; its predominant mechanism may simply be sedation. Flibanserin increased “sexually satisfying events” by less than one event a month (the event, by the way, need include neither an orgasm nor a partner).

The labeling of flibanserin reveals the absurdity of this “disease” and its treatment. In fact, hypoactive sexual desire disorder (HSDD) was invented by pharmaceutical manufacturers. We have written about how continuing medical education was used to establish this invented disease in the minds of clinicians. Stress, fatigue, boredom, children, medications, and a plethora of other factors unfixable by a pill can contribute to reduced libido.

Nonetheless, flibanserin is on its way to the US market, and will be available in mid-October. Flibanserin must be taken every day, and users must swear off alcohol as long as they are taking the drug. On the upside, if one drinks to unwind, flibanserin may be a fair substitute: a single dose of flibanserin is as sedating as four shots of alcohol. The U.S Food and Drug Administration was so concerned about potentially severe adverse effects when flibanserin was mixed with alcohol that they required the drug manufacturers to test the combination. In a stunning act of corporate nose-thumbing, Sprout Pharmaceuticals performed the alcohol-flibanserin interaction study in 25 subjects – only two of whom were women.

At the FDA advisory committee meeting that considered the drug in June 2015, the company claimed, implausibly, that they couldn’t identify more than two women who drank enough to fit eligibility requirements: more than 5 drinks a week. That’s right; they couldn’t find more than two women who regularly had a glass of wine with dinner. Although men are less susceptible to adverse effects of alcohol than women, the flibanserin cocktail felled several – four of the men in the alcohol interaction study fainted or experienced a steep drop in blood pressure.

The FDA will require prescribers to warn women not to consume alcohol with flibanserin, but alcohol is not the only interactor. Birth control pills, migraine medications, yeast medicines and many other medications increase flibanserin levels, increasing the risk of adverse events.

Less than 48 hours after flibanserin was approved, the drug was purchased by Valeant Pharmaceuticals for a billion dollars. An invented disease has spawned a real, and dangerous, treatment. Real money is at stake, and promotional efforts are likely to be robust. The FDA has failed American women in approving this drug. We can only hope that drug regulatory bodies elsewhere resist the siren call of flibanserin.